Question: Umaima starts counting at 31, and she counts by threes. If 31 is the 1st number that Umaima counts. what is the 9th number that she counts?
What is the first number that she counts? $31$ What is the second number that she counts? $\begin{align*}&31 + 3 \\ &= 34\end{align*}$ What is the third number that she counts? $\begin{align*}&31 + 3 + 3 \\ &= 31 + (2 \times 3) \\ &= 37\end{align*}$ What is the 9th number that she counts? $\begin{align*}&31 + (8\times3) \\ &= 31 + 24 \\ &= 55\end{align*}$